Design And Optimization Of Hight Performance Heat Exchange Device

Shell-and-tube heat exchanger is widely used in petroleum, chemical and other process industry, they take over the proportion of40%of the investment cost in process equipment, so accurate design of heat exchanger has great engineering application value, no matter for the equipment investment, or energy efficient utilization.In this paper, a set of method used for design of fixed tube plate heat exchanger, floating head heat exchanger and U-tube heat exchanger has been proposed, based on the contrast of different heat exchanger design methods. In this method, segmented computing is used with the concern of influence caused by the change of fluid physical property, heat exchanger is divided into several segment by the number of baffles and tube pass, take each segment as a small exchanger and then finish the design work. The key point of this method is to figure out the temperature distribution in the exchanger, a method used for the calculation of condensing temperature distribution is proposed in this paper, on the basis of non-phase change temperature calculation method, a profession physical property software is needed to get the correlation ship between temperature-enthalpy and temperature-vapor phase fraction.This design method needs a lot of iterative calculation, and calculation by Excel cannot guarantee the design accuracy, in this paper, design software is developed by using VB6.0and access database.Theinterface of this software is simple and the operation is convenient, which improves the design efficiency greatly. This software can be used for typedesign,it can judge the heat exchanger that users choose whether meet the process operating conditions. It also can be used for optimization design, the best result is figured out by the code of years cost or JF factor.In this paper, two actual project cases, tube side condensation heat transfer process and shell side boiling heat transfer process, are calculated. Contrast with the design results by HTRI, the errors are within20%, which prove the effectiveness and accuracy of this software.